Monday, July 18, 2016

What are bellows couplings?

A bellows coupling is a type of coupling design which consists of a thin walled, flexible corrugation (bellows) that is connected between two clamping hubs.  They are traditionally used for servo motion control applications that have high positioning accuracy, speed, and torque requirements.

Cross Section View of Bellows Coupling

What makes bellows couplings unique?
Bellows couplings are unique because of the construction of the bellows which can flex and compensate for minor shaft misalignments (axial, lateral, radial), while still providing a zero backlash and torsionally rigid connection.  They are a unique blend of rigidity and flexibility.

How to specify bellows couplings
To specify a bellows coupling, the first parameters we typically look at are the torque and connecting shaft sizes which will help to give a general sense of the coupling size.  The nominal torque rating (continuous torque transmission)  of the coupling should be greater than the peak torque of the application to ensure a secure connection.  We then check the connecting shaft sizes which  must also be within the acceptable range of the coupling.  If the shaft diameter is smaller than the specified range on the coupling, the torque transmission value of the coupling can decrease.  From there, we check other application specific parameters which include the speed, shaft alignment, temperature, and drive resonance.  We need to make sure they are within the coupling specifications, if not, we look to apply a safety factor when applicable; otherwise we select a different coupling size, or design. 

Bellows couplings applications examples
When introduced, bellows couplings were first widely accepted in the Machine Tool industry for spindle drives.  Since then usage has expanded to a vast number of industries including Automotive, General Automation & Assembly, Material Handling, Medical, Packaging, Robotics, to name a few.

For more information about couplings, visit

Monday, March 21, 2016

GAM Introduces the SPH Flange Gearbox

SPH Flange Gearbox

GAM, a manufacturer of high precision gear reducers, servo couplings, and linear mounting kits, introduces the SPH Flange planetary gearbox.

The SPH Flange (SPH-F) is the first high performance inline flange gearbox from GAM.  Based around high precision helical gear technology, the SPH Flange is produced to the elevated standard of quality and reliability customers have come to expect from GAM’s SPH product line.  The helical gears are precision cut and ground for extremely quiet and smooth torque transmission with a standard backlash rating of <3 arcmin for single stage ratios.  For applications that require more precision, the gearbox can assembled for further reduced backlash at <1 arcmin.

“We are excited to launch the SPH-F as it is the first high precision inline flange gearbox in our product offering,” said Mike Parzych, Product Marketing Manager at GAM. “We’ve already had some great customer successes with the product and are looking forward to further market acceptance.”

The compact SPH-F gearbox can be used when space is limited and the ISO 9409 compatible output flange allows for easy mounting of machine elements such as pinions, pulleys, or other adapters.  To accommodate direct connection to machines, the SPH-F has strong taper roller bearings set at a wide distance and a fully supported planet carrier for high load carrying capacity.  The ring gear is machined directly into a single piece steel housing for improved torsional rigidity.  Currently offered in three frame sizes, the SPH-F is rated for up to 450Nm nominal and 675Nm acceleration torque in the largest size.

Please visit for more information on the SPH-F including fully configurable CAD models.


A PDF of the Press Release - GAM Introduces the SPH Flange Gearbox

About GAM
GAM is your complete source for Gear Reducers, Servo Couplings, Linear Mounting Kits, and other innovative products used in automation technology. With one of the largest product offerings in the motion control industry as well as the engineering expertise and capabilities to develop customized solutions, GAM can help with your application.  Being flexible to meet the needs of customer requests and great service are what set them apart from the rest.  For more information visit:  GAM is also on Twitter!/GAM_Gear and Facebook

Thursday, February 19, 2015

Introducing the EDC Elastomer Drive Shaft Coupling

drive shaft coupling edc
The EDC is designed, machined, and assembled to order in Mt. Prospect, IL.  CAD models are online and easily configurable for download in minutes.  The EDC is available in four sizes based on the torque rating: 25Nm, 35Nm, 80Nm, and 110Nm. Derived from the design of GAM's EKC elastomer coupling, the EDC is a quality drive shaft solution at an economical price for this torque segment.
Split Hub Design

drive shaft coupling split hub

The EDC has a split hub construction for easy installation.  This design feature allows the coupling to be installed by placing it directly over the shafts that need to be connected.  The shafts can remain fixed and do not need to be retracted during installation to get proper shaft engagement.

GAM's Drive Shaft Lineup

distance coupling

The EDC is the latest addition to GAM's family of drive shaft coupling solutions. GAM now has three options to cover various motion applications and torque requirements.

Option 1 - EDC
The EDC is rated up to 110Nm of torque and was designed to be an economical drive shaft option, suitable for general motion / lower torque applications.

Option 2 - EKZ
The EKZ is rated up to 700Nm of torque and is the next progression in GAM's drive shaft coupling range.  While still an elastomer style drive shaft coupling, the EKZ is suitable for higher torque applications.

Option 3 - WDS
The WDS is rated up to 1600Nm of torque and is GAM's highest performing drive shaft coupling, intended for dynamic applications that require high positioning accuracies.  It features a torsionally rigid bellows design which yields a 1208% increase in torsional rigidity over an elastomer style drive shaft coupling of a comparable torque rating.

Monday, July 21, 2014

Spiral Bevel Gearboxes - When Size Matters

spiral bevel gearboxes
With torques up to 4,440Nm, frame sizes up to 350mm, and power ratings up to 267kW, the V-Series is tough enough to handle demanding power transmission applications.   

For miniature mechatronic applications when space is a premium, our L-Series is the best option available on the market. The housings are manufactured from high-strength aluminum which means they are light weight, dissipate heat efficiently, and resist corrosion.       

Considerations for Continuous Running Spiral Bevel Gearbox Applications

spiral bevel gearboxes for continuous running applications

Spiral bevel gearboxes are often selected for continuous running applications due to their high efficiency ratings up to 96%.  However, in low ratio configurations, the input and output shafts will be running at higher speeds resulting in greater heat generation.  A properly sized gearbox will be able to dissipate the heat effectively and the temperature will stabilize to an acceptable level. 

While there are several factors that impact the gearbox temperature, two important considerations are the input running speed and mounting orientation.  These two criteria will help to determine if minor adjustments can be made to the gearbox during assembly to aid heat dissipation.  Adjustments can be made to the backlash, bearing pre-loads, lubrication (volume/viscosity), and a vent filter or oil cooling system may ultimately be required.  Spiral bevel gearboxes that cannot be adjusted may not be suitable for continuous running applications. 

The chart above graphs the housing temperature of a V-Series gearbox (blue-dash) and a competitive spiral bevel gearbox (red-dotted) of comparable size.  Both gearboxes were 1:1 ratios and tested at a continuous input speed of 1,800 RPM for 2 hours.  Because the V-Series gearbox (blue-dash) was sized and assembled for the continuous application, it was able to dissipate the heat properly allowing the temperature to stabilize to an acceptable value of approximately 80°C.  The competitive spiral bevel gearbox (red-dotted) could not dissipate the heat and the gearbox temperature continued to rise to 140°C before the test was terminated to avoid eventual failure.

To help prevent a spiral bevel gearbox from failing due to overheating, it is important to specify the duty cycle, input running speed, and mounting orientation.  Those criteria are specified in GAM's V-Series type code to help ensure the gearbox is ordered and assembled to best suit each application. 

GAM Spiral Bevel Gearboxes: Dependable by Design

spiral bevel gearboxes
1. Housing: Sturdy cast iron housing (Aluminum in size 35mm and 45mm) - all 6 sides can be used for mounting 
2. Bearings:  Deep groove ball bearings handle axial and radial loading. (Reinforced and taper roller options available)
3. Spiral Bevel Gearing:  Precision cut, hardened, and lapped in pairs for ideal tooth contact. Mathematically precise ratios from 1:1 to 6:1
4. Input:  Available with shaft input or integrated motor adapter and coupling to easily mount to any IEC, NEMA, or servo motor
5. Output:  Solid shaft with key or keyed hollow shaft are standard. (Smooth shaft or shrink disc clamping available)
6. Seals:  Lubricated for life and protected with high quality NBR seals. (Viton® and FPM seals available) 

Carefully engineered and crafted with high quality materials, GAM spiral bevel gearboxes are robust and can handle high shock loads. Since they are maintenance free and lubricated for life, have confidence knowing that they are built to last. Put one onto your machine and forget about it!

Tuesday, July 8, 2014

High School Students in Career Exploration Course Visit GAM

Students enrolled in a Summer Career Exploration Course sponsored by Oakton Community College and NSERVE, visited GAM to see what a future in engineering and advanced manufacturing could be like.  Through the Career Exploration Course, students get first hand experience of the careers and work environments in the areas of their choice.  The program is open to sophomores, juniors, and seniors from nearby high schools.

What are Engineers?  
What things do Engineers build? 
What skills must one have to become an Engineer?
What is the job outlook like for Engineers?  

These were some of the questions answered in an interactive presentation with the students.  Students also learned how important internships are to discover their interests in addition to getting an upper hand at landing a job after college.  After the presentation, the students were split into three groups for a factory tour to see different functions at GAM including design engineering, machining, and assembly.

This is the third STEM program that GAM has been involved in this year alone.  In addition to participating in educational programs such as this, GAM often has internships available for high school students interested in engineering, manufacturing, and business.  For factory tours or information on internships, please contact  For more information about the Career Exploration Course, please visit